Climate: August 2026 is the hottest August on record

August 2026 has been declared the hottest August ever recorded globally, according to the European Copernicus Climate Change Service, which made the announcement on Thursday, September 10. The average surface air temperature reached 16.96 °C, which is 1.65 °C above the estimated pre-industrial average from 1850 to 1900.

The month also tied the record for the hottest month across all times of the year, matching July 2023. This marks the first month since November 2025 to exceed the pre-industrial reference by more than 1.5 °C, a threshold closely monitored under the Paris Agreement.

However, this monthly exceedance does not indicate that the 1.5 °C target set by the Paris Agreement has been surpassed in a climatic sense. This threshold pertains to a long-term average. Over the twelve months from September 2025 to August 2026, the global average temperature was 1.48 °C above the pre-industrial level, according to Copernicus.

The oceans also reached exceptional levels. The average sea surface temperature outside polar regions hit 21.07 °C in August, a record for that month and equal to the maximum monthly level observed in March 2024. On August 24 and 25, this daily average peaked at 21.11 °C.

These anomalies were accompanied by episodes of drought and heat across vast areas. Copernicus reported drier-than-normal conditions in the Maghreb, the Horn of Africa, and parts of Southern Africa, while Western Europe is emerging from its hottest summer on record.

A record summer in Western Europe

Between June and August 2026, the average temperature in Western Europe reached 21.69 °C, which is 2.54 °C above the 1991-2020 average. The season surpassed the previous regional record set in 2003, following a series of early and persistent heatwaves since May.

Drought has also impacted several European regions. The Rhine, Danube, Vistula, Seine, and Rhône rivers experienced exceptionally low flows during certain periods of the summer, while soils remained very dry in parts of the west, center, and east of the continent.

Very warm oceans and a strengthening El Niño

Copernicus attributes these records to the combination of climate warming caused by fossil fuel emissions and particularly high temperatures in the tropical Pacific. These conditions have also contributed to the intensification of seasonal fires in Indonesia. The El Niño phenomenon, already established, is enhancing ocean surface temperatures and can alter rainfall and heat patterns in many regions worldwide.

The World Meteorological Organization estimates that El Niño has a nearly 100% probability of persisting until the December 2026 to February 2027 period. The agency warns that a very intense episode could heighten the risks of droughts, floods, and other extreme weather events depending on the regions.